Initializing camera subsystem for face detection based on sensor inputs

ABSTRACT

In one embodiment, a method comprises monitoring one or more sensors of a computing device that is in a locked state and is associated with an authorized user of a social-networking system, identifying, based on information associated with the authorized user, content to be downloaded from the social-networking system, and downloading the identified content from the social-networking system, wherein the identified content is stored for display after the computing device is unlocked. The downloading may be in response to determining that an operation to unlock the computing device is imminent, and the content may include commonly-viewed content. The downloading may include downloading one or more notifications from the social-networking system. The downloading may be based on one or more previous habits of the authorized user. The information associated with the authorized user may include information indicating that the authorized user habitually checks one or more sites or feeds.

PRIORITY

This application is a continuation under 35 U.S.C. § 120 of U.S. patentapplication Ser. No. 15/423,411, filed 02 Feb. 2017, which is acontinuation under 35 U.S.C. § 120 of U.S. patent application Ser. No.13/229,327, filed 09 Sep. 2011, now U.S. Pat. No. 9,596,084.

TECHNICAL FIELD

This disclosure generally relates to mobile electronic devices and morespecifically relates to automatically priming the camera subsystem of amobile device based on detected events in preparation for an image-basedunlocking operation.

BACKGROUND

A mobile electronic device, such as a smartphone, tablet, notebookcomputer, etc., may have multiple operation states. For example, while amobile device is not being used by its user, it may be in a power-savingor sleep state (e.g., the screen is dim or dark) in order to decreasepower-consumption level and prolong battery life. In some cases, themobile device may also be in an input locked state (e.g., thetouchscreen or keypad of the mobile device is locked) so that the mobiledevice does not perform unintentional or accidental operations. In othercases, the mobile device may be security locked, such that a user isrequired to provide a correct password or personal identification number(PIN) in order to unlock and use the device. The advent of optical faceor iris detection and recognition obviates the need for physicalmanipulation of a touchscreen or keypad to unlock mobile devices.

SUMMARY

This disclosure generally relates to mobile electronic devices and morespecifically relates to automatically initializing the camera subsystemof a mobile electronic device based on a detected sensor inputs.

In particular embodiments, a mobile electronic device detects theangular acceleration about one or more axis from an accelerometer orgyrometer in a sensor hub indicative of a user picking up the mobiledevice. In particular embodiments, a mobile device detects a transitionfrom a low-light to high-light environment via a light sensor in asensor hub indicative of a user removing the mobile device from apocket, bag, or case. In particular embodiments, a mobile device detectsa transition from having nearby objects to having no nearby objects viaa proximity sensor indicative of the mobile device being removed from apocket, bag, or case. In particular embodiments, a mobile device detectsa transition from a low volume to high volume environment via amicrophone indicative of the mobile device being removed from a pocket,bag, or case. In particular embodiments, a mobile device detects atransition from muffled audio to clear audio via a microphone indicativeof removal of the mobile device from a pocket or bag. In particularembodiments, any combination of the previous sensor transitions may beutilized to determine that the user is about to look at the mobiledevice, and may trigger an operation to initialize the camera subsystemof the mobile device. In particular embodiments, upon camerainitialization, the camera continuously monitors its input for thepresence of a face. In particular embodiments, facial recognition isutilized to unlock the mobile device. In particular embodiments, thecamera captures a photo of the user and prompts the user as to whetherhe or she would like to use the photo as a profile picture on a socialnetwork. In particular embodiments, the mobile device automaticallyuploads the captured photo to the user's profile page on a socialnetwork.

These and other features, aspects, and advantages of the disclosure aredescribed in more detail below in the detailed description and inconjunction with the following figures.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example mobile electronic device.

FIG. 2 illustrates the exterior of an example mobile device.

FIG. 3 illustrates an example method for automatically initializing thecamera subsystem of a mobile device in response to sensor inputsindicative of an impending unlock operation.

FIG. 4 illustrates an example computer system.

DESCRIPTION OF EXAMPLE EMBODIMENTS

This disclosure is now described in detail with reference to a fewembodiments thereof as illustrated in the accompanying drawings. In thefollowing description, numerous specific details are set forth in orderto provide a thorough understanding of this disclosure. However, thisdisclosure may be practiced without some or all of these specificdetails. In other instances, well known process steps and/or structureshave not been described in detail in order not to unnecessarily obscurethis disclosure. In addition, while the disclosure is described inconjunction with the particular embodiments, it should be understoodthat this description is not intended to limit the disclosure to thedescribed embodiments. To the contrary, the description is intended tocover alternatives, modifications, and equivalents as may be includedwithin the spirit and scope of the disclosure as defined by the appendedclaims.

A mobile electronic device, such as a smartphone, tablet or notebook,may have multiple operation states. For example, when a mobile devicehas not being used by its user for a period of time (e.g., a fewseconds), it may enter into a power-saving state. At the power-savingstate, the mobile device may operate at a lower power level in order tosave energy and prolong battery life. The screen of the mobile devicemay be dim or dark. To bring the mobile device out of the power-savingstate into the normal power state, the user may need to perform anaction with the mobile device (e.g., pushing the power button of themobile device). In some cases (e.g., after the mobile device is in thepower-saving state for a few seconds), the mobile device may also enterinto an input-lock state. At the input-lock state, the input component(e.g., keypad or touch-sensitive screen) of the mobile device may belocked to prevent accidental inputs causing unintentional operations. Tounlock the keypad or screen of the mobile device, the user may need toperform another action with the mobile device. For example, if themobile device has a keypad, the user may need to push a key. If themobile device has a touch-sensitive screen, the user may need to press acontrol to power up the device and make a swipe gesture on the screen.In addition, the mobile device may have a security-lock state. At thesecurity-lock state, the mobile device is password or PIN (PersonalIdentification Number) locked to prevent unauthorized access to andusage of the mobile device. To unlock the mobile device, the user mayneed to enter the appropriate password or PIN. When the mobile device isbeing actively used by its user, it may be in a normal operation state(e.g., operating at the full power level and ready to receive userinputs). In some cases, the mobile device may be in an operation statewhere its audio output is turned on, an operation state where its audiooutput is turned off, or an operation state where its audio output is ina specific mode (e.g., loud, quiet, vibrate, etc.). Other operationstates may also be possible, and this disclosure contemplates anyapplicable operation state.

At any given time, a mobile device may be in any one of the operationstates, depending on, for example, whether the user is currently usingthe mobile device, the amount of time passed since the user's last useof the mobile device, the location of the mobile device (e.g., in acarrying case, in the user's pocket or purse, etc.).

For example, suppose that the user has not used his mobile device (e.g.,an Apple iPhone) for some time and the mobile device has been stored inthe user's pocket. In this case, the mobile device is most likely in thepower-saving state to save battery as well as the input-lock state toprevent accidental inputs. In addition, the mobile device may also be inthe security-lock state to prevent unauthorized access to the mobiledevice. Further suppose that the user now wishes to use his mobiledevice. The user may need to: (1) take the mobile device out of hispocket; (2) push the power button to bring the mobile device out of thepower-saving state; and (3) swipe the touch screen to unlock the inputcomponent of the mobile device. In addition, if the mobile device issecurity locked as well, then the user also needs to enter the passwordor PIN to unlock the mobile device. At least, the user needs to performa few actions, which may take several seconds, before the mobile deviceis ready to be used. Considering that such a sequence of actions mayneed to be performed several times a day (e.g., each time the user needsto use his mobile device after not using the mobile device for a periodof time), it may become inefficient and time consuming.

Recent advances in face recognition technology greatly simplifies theunlocking process by utilizing a front-facing camera in a mobile deviceto capture an image of the user's face, match it against a knowndatabase of authorized users, and unlock the phone if the current user'sface matches one of the faces in the database. Other camera-basedimplementations utilize iris detection rather than facial detection.However, current implementations, such as the RecognizeMe applicationfor iOS or Recognizr, Visidon, and BioLock applications for GoogleAndroid OS, still require that the user swipe the touchscreen toinitiate the process. Additionally, current implementations onlyactivate the camera subsystem after the user has swiped the touchscreen,resulting in delays while the operating system initializes and readiesthe front-facing camera for image capture.

Therefore, particular embodiments may automatically initialize thecamera subsystem of a mobile device in the locked mode in anticipationof a likely unlock operation based upon one or more inputs to its sensorhub. In particular embodiments, a mobile electronic device, such as amobile device, may include various types of sensors, such as, forexample and without limitation, touch sensors (disposed, for example, ona display of the device, the back of the device and/or one or morelateral edges of the device) for detecting a user touching the surfaceof the mobile electronic device (e.g., using one or more fingers),accelerometer for detecting whether the mobile electronic device ismoving and the speed of the movement, thermometer for measuring thetemperature change near the mobile electronic device, proximity sensorfor detecting the proximity of the mobile electronic device to anotherobject (e.g., a hand, desk, or other object), light sensor for measuringthe ambient light around the mobile electronic device, imaging sensor(e.g., camera) for capturing digital images of objects near the mobileelectronic device, location sensors (e.g., Global Positioning System(GPS)) for determining the location (e.g., in terms of latitude andlongitude) of the mobile electronic device, near field communication(NFC) sensors, Bluetooth sensors, etc. This disclosure contemplates thata mobile electronic device may include any applicable type of sensors.These sensors may provide various types of sensor data, which may beanalyzed to determine that the user has picked up his or her mobiledevice in the locked state and will be imminently performing an unlockoperation.

FIG. 1 illustrates an example mobile electronic device 100. Inparticular embodiments, mobile electronic device 100 may includeprocessor 110, memory 120, communication component 130 (e.g., antennaand communication interface for wireless communications), and a numberof sensors 150 of various types (e.g., touch sensor, accelerometer,thermometer, proximity sensor, light sensor, imaging sensor, etc.). Inparticular embodiments, a sensors hub 140 may optionally be included inmobile device 100. Sensors 150 may be connected to sensors hub 140,which may be a low power-consuming processor that controls sensors 150,manages power for sensors 150, processes sensor inputs, aggregatessensor data, and performs certain sensor functions. In addition, inparticular embodiments, some types of sensors 150 may be connected to acontroller 160. In this case, sensors hub 140 may be connected tocontroller 160, which in turn is connected to sensor 150. Alternatively,in particular embodiments, there may be a sensor monitor in place ofsensors hub 140 for managing sensors 150.

In particular embodiments, mobile electronic device 100 (e.g., a mobiledevice) may have a touchscreen as its input component. FIG. 2illustrates the exterior of an example mobile device 200. Mobile device200 has six sides: front, back, top, bottom, left, and right. Touchsensors may be placed anywhere on any of the six sides of mobile device200. For example, in FIG. 2, a touchscreen incorporating touch sensors210A is placed on the front of mobile device 200. The touchscreen mayfunction as an input/output (IO) component for mobile device 200. Inaddition, touch sensors 210B and 210C are placed on the left and rightsides of mobile device 200, respectively. Touch sensors 210B and 210Cmay detect a user's hand touching the sides of mobile device 200. Inparticular embodiments, touch sensors 210A, 210B, 210C may beimplemented using resistive, capacitive, and/or inductive touch sensors.The electrodes of the touch sensors 210A, 210B, 210C may be arranged ona thin solid piece of material or a thin wire mesh. In the case ofcapacitive touch sensors, there may be two types of electrodes:transmitting and receiving. These electrodes may be connected to acontroller (e.g., controller 160 illustrated in FIG. 1), which may be amicrochip designed to drive the transmitting electrodes with electricalpulses and measure the changes in capacitance from the receivingelectrodes caused by a user's touches in order to detect the locationsof the user touches.

Of course, mobile device 200 is merely an example. In practice, a devicemay have any number of sides, and this disclosure contemplates deviceswith any number of sides. The touch sensors may be placed on any side ofa device.

In particular embodiments, mobile device 200 may have a proximity sensor220 (e.g., an infrared LED (light-emitting diode)) placed on either itsfront or back side. Proximity sensor 220 may be able to supply sensordata for determining its proximity, and thus the proximity of mobiledevice 200, to another object.

FIG. 3 illustrates an example method for automatically initializing thecamera subsystem of a mobile electronic device (e.g., mobile electronicdevice 100 illustrated in FIG. 1 or mobile device 200 illustrated inFIG. 2) based on a detected sensor inputs. In particular embodiments, amobile electronic device may include any number of sensors of varioustypes. These sensors may provide various types of sensor data. Aprocessor within the mobile device (either processor 110, sensor hub140, or controller 160) continuously monitors the sensors for inputs toone or more sensors. Upon receiving sensor data from one or more suchsensors, as illustrated in STEP 310, the sensor data may be processedand analyzed to estimate or detect the whether an unlock operation isimminent, as illustrated in STEP 320. If the processor determines thatan unlock operation is imminent, at STEP 330 the processor automaticallyinitializes the camera subsystem in preparation of image capture. AtSTEP 340, mobile device 200 applies facial recognition algorithms todetermine whether a face is present in the capture area of the lens.After a predetermined period of time, if no face is detected, theprocess times out and the system returns to the unlock state. At STEP350, upon detection of a face, mobile device 200 begins opticalauthentication procedures, such as matching the captured face or iris toa prestored image of an authenticated user's face or irises. The stepsillustrated in FIG. 3 are explained in more detail using the followingexamples.

As an example, suppose that a user has a mobile device that is stored inthe user's pocket. Thus, the mobile device is currently in the lockedstate. When the user desires to use the mobile device, the user mayreach into his pocket, grab hold of the mobile device, and take it outof the pocket. In particular embodiments, while in the locked state, aprocessor of the device (such as a main CPU or a controller) mayperiodically wake up (for example, every 100 milliseconds) and poll oneor more sensors to detect if a user has picked the device.Alternatively, in particular embodiments, the CPU may be waken up byother means without having to specifically poll the sensors. Forexample, the CPU may be woken up through an interrupt signal or event orby dumb circuit.

In particular embodiments, in addition to the front side, the mobiledevice may have touch sensors on the left and right sides. Optionally,the mobile device may also have touch sensors on the back, top, orbottom side (e.g., mobile device 200 illustrated in FIG. 2). Thus, asthe user's hand touches the mobile device to grab hold of it, the touchsensors may detect the user's fingers or palm touching the mobiledevice. The touch-sensor data may be analyzed to determine when andwhere the user has touched the mobile device. When the user touches themobile device, it may be an indication that the user may wish to use themobile device.

In particular embodiments, the placement of touch sensors on the left,right, top, and/or bottom sides may indicate whether a user is touchingboth sides of the mobile device (i.e., the user is grasping the mobiledevice). Thus, the touch sensors can differentiate grasping the mobiledevice in addition to simply touching it. In particular embodiments,being able to detect that the user has grasped the mobile device mayyield a more accurate, and thus better, indication of the user'sintention.

In particular embodiments, the mobile device may have an accelerometerin addition or instead of the touch sensors on the left and right sides.Again, sometimes, the user may put his hand in the pocket where themobile device is stored and thus touch the mobile device even when theuser does not intend to use the mobile device at that time. If themobile device also has an accelerometer, the sensor data provided by theaccelerometer may also be used to estimate whether the user intends touse the mobile device. When the mobile device is stored in the user'spocket, it may move as the user moves. However, such movements usuallyare relatively slow. On the other hand, when the user grabs hold of themobile device and takes it out of the pocket to bring it in front of theuser's face, there may be a relatively sudden increase in the movementspeed of the mobile device. This change in the mobile device's movementspeed may be detected based on the sensor data supplied by theaccelerometer. In particular embodiments, upon detecting that there is asignificant increase in the speed of the mobile device's movement,either by itself or in addition to detecting that the user has touchedthe mobile device, the mobile device processor may determine that anunlock operation is imminent.

In particular embodiments, the mobile device may have a Gyrometer inaddition or instead of the touch sensors on the left and right sides. AGyrometer, also known as a gyroscope, is a device for measuring theorientation along one or more axis. In particular embodiments, aGyrometer may be used to measure the orientation of the mobile device.When the mobile device is stored in the user's pocket, it may staymostly in one orientation. However, when the user grabs hold of themobile device and takes it out of the pocket to bring it in front of theuser's face, there may be a relatively sudden change in the orientationof the mobile device. The orientation of the mobile device may bedetected and measured by the gyrometer. If the orientation of the mobiledevice has changed significantly, it may be another indication that theuser may have taken the device out of his pocket, or from a flatsurface, such as resting on a table, to a more vertical orientation, aswhen a users lifts his or her phone from a table to view near the user'sface.

In particular embodiments, the mobile device may have a light sensor.When the mobile device is stored in the user's pocket, it is relativelydark around the mobile device. On the other hand, when the user bringsthe mobile device out of his pocket, it may be relatively bright aroundthe mobile device, especially during day time or in well-lit areas. Thesensor data supplied by the light sensor may be analyzed to detect whena significant change in the ambient light level around the mobile deviceoccurs. In particular embodiments, upon detecting that there is asignificant increase in the ambient light level around the mobiledevice, either by itself or in addition to detecting that the user hastouched the mobile device or in addition to detecting that there is asignificant increase in the speed of the mobile device's movement, themobile device processor may ascertain that an unlock operation isimminent.

In particular embodiments, the mobile device may have a proximitysensor. The sensor data supplied by the proximity sensor may be analyzedto detect when the mobile device is in close proximity to a specificobject, such as the user's hand. For example, as illustrated in FIG. 2,mobile device 200 may have an infrared LED 220 (i.e., proximity sensor)placed on its back side. When the user holds such a mobile device in hishand, the palm of the user's hand may cover infrared LED 220. As aresult, infrared LED 220 may detect when the user's hand is in closeproximity to mobile device 200. In particular embodiments, upondetecting that the mobile device is in close proximity to the user'shand, either by itself or in combination with other types of sensorindications, the mobile device may determine that an unlock operation isimminent.

Alternatively to or in conjunction with a back-facing proximity sensor,mobile device 200 may have a front-facing proximity sensor, to detectwhether the front of the device is near an object (such as a face whenused for voice communications). In particular embodiments, when thephone is in a lock mode, the presence of an object to the front facingproximity sensor may indicate that mobile device 200 is in a pocket,bag, or case, and a sudden transition from a positive proximity sensorreading (object detected) to a negative proximity sensor reading (noobjects detected) may indicate that mobile device 200 has been taken outof the pocket, bag, or case, and may signify an impending unlockoperation.

In particular embodiments, sensor hub 140 may include a microphone thatperiodically captures ambient audio waveforms. Transitions from quietenvironments to noisy environments occur with some regularity, but,coupled with the other sensor transitions as described above, they mayindicate that mobile device 200 was removed from a bag, pocket, purse,or other type of carrying case and indicate that an unlock operation isimminent. Additionally, waveform analysis may be performed by one ormore processors in mobile device 200 to determine whether sound ismuffled or clear. In particular embodiments, this waveform analysis isperformed through the use of Fast Fourier Transforms, wavelet analysis,or other frequency-domain analysis. For example, muffled sound iscommonly associated with high amplitude low frequency bands and lowamplitude high frequency bands. This disclosure contemplates anysuitable manner of detecting muffled and clear audio waveforms. Inparticular embodiments, transitions from muffled to clear audioenvironments indicates that an unlock operation is imminent.

A mobile device may have any number of sensors of various types, andthese sensors may supply different types of sensor data. Differentcombinations of the individual types of sensor data may be used togetherto determine whether an unlock operation is imminent. Sometimes, usingmultiple types of sensor data in combination may yield a more accurate,and thus better, estimation of the user's intention to unlock the mobiledevice at a given time than only using a single type of sensor data.Nevertheless, it is possible to estimate the user's intention to unlocka mobile device using a single type of sensor data (e.g., touch-sensordata).

One or more combinations of the various sensor data is generallysufficient to capture all the possible scenarios in which a user maywish to unlock his or her mobile device, including but not limited to:removing the mobile device from a pocket; removing the mobile devicefrom a bag or case; lifting a mobile device from a flat surface such asa table; lifting the mobile device from a docked position; flipping overthe mobile device; and the like. This disclosure contemplates anysuitable combination of sensor inputs in determining whether the user ofa mobile device intends to unlock the mobile device.

In particular embodiments, the identity of the user currently handlingthe mobile device may be verified. If the user currently handling themobile device is the true owner of the mobile device, the mobile devicemay be unlocked automatically. On the other hand, if the identity of theuser currently handling the mobile device cannot be verifiedsatisfactorily, the user may be prompted and required to provide apassword or PIN in order to unlock and use the mobile device.

There may be various means to verify a user's identity. As the userbrings the mobile device in front of his face, the camera of mobiledevice 200 may analyze captured digital images of the objects in frontof its lens in order to detect and capture the user's face. These imagesmay be analyzed using one or more suitable facial recognition algorithmsto locate and compare the user's face to the face of the owner of themobile device (e.g., the face stored on file in connection with themobile device). If there is a sufficient amount of similarity betweenthe two faces (i.e., a match), then the user currently handling themobile device may be verified as the actual owner of the mobile device,and the mobile device may be unlocked without asking the user toexplicitly provide a password or PIN. The image representing the face ofthe owner of the mobile device may be stored on the mobile device itselfor elsewhere (e.g., on a server accessible to the mobile device). Insome implementations, multiple different images of the user's face maybe stored. In some implementations, the captured imaged of the user'sface (if a match is successful) may be stored for later comparison. Insome implementations, a set of captured images of the user's face may bestored an used in a comparison. The set of captured images can be storedin a ring or circular buffer structure where the last captured imageoverwrites the oldest image in the set of images.

In particular embodiments, the user may authorize guest users, and themobile device may store photos of authorized guest users' faces forcomparison. In particular embodiments, the user may define a set ofaccess rights or use privileges for each guest user, or may apply aglobal setting to all guest users.

In particular embodiments, the camera of mobile device 200 may analyzecaptured digital objects in front of its lens in order to capture theuser's iris. Iris-recognition algorithms may be utilized to match anauthorized user's iris to the captured iris. If there is a sufficientamount of similarity between the two irises, then the user currentlyhandling the mobile device may be verified as the actual owner of themobile device.

In particular embodiments, the user of the mobile device may be a memberof a social-networking system. A social network, in general, is a socialstructure made up of entities, such as individuals or organizations,that are connected by one or more types of interdependency orrelationships, such as friendship, kinship, common interest, financialexchange, dislike, or relationships of beliefs, knowledge, or prestige.In more recent years, social networks have taken advantage of theInternet. There are social-networking systems existing on the Internetin the form of social-networking websites. Such social-networkingwebsites enable their members, who are commonly referred to as websiteusers, to perform various social activities. For example, thesocial-networking website operated by Facebook, Inc. at www.facebook.comenables its users to communicate with their friends via emails, instantmessages, or blog postings, organize social events, share photos,receive news of their friends or interesting events, play games, etc.

The user may have a profile with the social-networking system thatincludes information relevant to the user (e.g., demographic data,social connections and activities, interests, hobbies, etc.). Inparticular embodiments, the information found in the user's profile mayalso be used to help determine the user's intention with respect to themobile device at a given time or estimate the user's identity. Forexample, if, based on the user's calendar stored with thesocial-networking system, it may be determined that the user isattending an event (e.g., a meeting), then the mobile device may betransitioned to a state where the screen is turned off and the inputcomponent is locked. As another example, it may be determined, based onthe information available with the social-networking system, that theuser is with his social connections (e.g., friends) at a given time andlocation. If the mobile device is in an atypical location for its owner,but at the same time, several of the owner's family members or friendsare also there, this may suggest that the mobile device is with its trueowner, in which case, the device may be unlocked without requiring apassword or PIN. On the other hand, if the mobile device is in anatypical location and none of its owner's social connections is there, apassword or PIN may be required to unlock the device to ensure that theuser of the device is indeed its true owner.

In particular embodiments, mobile device 200 may use the image utilizedfor facial recognition unlocking on the social network. In particularembodiments, the mobile device may prompt the user as to whether he orshe would like to update the user's profile picture on the socialnetwork. Upon an affirmative confirmation that the user would like touse the newly captured image as a profile picture, mobile device 200 mayautomatically upload the picture to the social network via a wirelessdata network. In particular embodiments, mobile device 200 automaticallyuploads the captured image as the user's new profile picture. Inparticular embodiments, mobile device 200 uploads the newly-capturedimage into a special album on the user's profile, thus generating aslideshow of facial recognition photos. In particular embodiments, thisslideshow may be converted into a video documenting how the user hasaged or progressed over a significant period of time. This disclosurecontemplates any suitable manner of leveraging the facial recognitionimage on the social networking system.

In particular embodiments, detection of an impending unlock process mayaffect the settings of the user account associated with mobile device200 on a social networking system. For example, a social networkingsystem may include one or more instant messaging clients. After a periodof inactivity, the user's presence on the instant messaging system maybe dropped or altered to an “idle” state. However, upon mobile device200 determining that sensor inputs indicate the user had picked upmobile device 200 and will be looking at the screen, mobile device 200may, either prior to or after authentication, update or alter the user'sonline status to “available” or “active.” In particular embodiments, thephoto captured by mobile device 200 for use in facial recognition may beuploaded as the user's instant messaging avatar.

In particular embodiments, mobile device 200 may perform various actionsin anticipation of likely actions following an unlock event. Forexample, upon determining that an unlock event is imminent, mobiledevice may begin to download notifications and commonly viewed content,such as a newsfeed, from a social networking system. In particularembodiments, the actions may be tailored to the specific user based onprevious habits. For example, if mobile device 200 determines that theuser of the device habitually checks certain news sites or RSS feedsevery time the user unlocks the phone, mobile device 200 may begin toautomatically pull content from the sites when an unlock operation isimminent. In particular embodiments, the time of day and day of week mayalso affect which actions mobile device 200 initiates upon detecting animminent unlocking operation. In particular embodiments, the user'slocation may affect what actions are performed by mobile device 200. Forexample, if the user has moved to an area that is neither his home norhis office, mobile device 200 may begin pulling nearby points ofinterest for a check-in operation. In particular embodiments, when theuser has traveled greater than a predetermined distance, mobile devicemay begin pulling content from the social network for an “around me”page.

Particular embodiments may be implemented on one or more computersystems. FIG. 4 illustrates an example computer system 400. Inparticular embodiments, one or more computer systems 400 perform one ormore steps of one or more methods described or illustrated herein. Inparticular embodiments, one or more computer systems 400 providefunctionality described or illustrated herein. In particularembodiments, software running on one or more computer systems 400performs one or more steps of one or more methods described orillustrated herein or provides functionality described or illustratedherein. Particular embodiments include one or more portions of one ormore computer systems 400.

This disclosure contemplates any suitable number of computer systems400. This disclosure contemplates computer system 400 taking anysuitable physical form. As example and not by way of limitation,computer system 400 may be an embedded computer system, a system-on-chip(SOC), a single-board computer system (SBC) (such as, for example, acomputer-on-module (COM) or system-on-module (SOM)), a desktop computersystem, a laptop or notebook computer system, an interactive kiosk, amainframe, a mesh of computer systems, a mobile telephone, a personaldigital assistant (PDA), a server, or a combination of two or more ofthese. Where appropriate, computer system 400 may include one or morecomputer systems 400; be unitary or distributed; span multiplelocations; span multiple machines; or reside in a cloud, which mayinclude one or more cloud components in one or more networks. Whereappropriate, one or more computer systems 400 may perform withoutsubstantial spatial or temporal limitation one or more steps of one ormore methods described or illustrated herein. As an example and not byway of limitation, one or more computer systems 400 may perform in realtime or in batch mode one or more steps of one or more methods describedor illustrated herein. One or more computer systems 400 may perform atdifferent times or at different locations one or more steps of one ormore methods described or illustrated herein, where appropriate.

In particular embodiments, computer system 400 includes a processor 402,memory 404, storage 406, an input/output (I/O) interface 408, acommunication interface 410, and a bus 412. In particular embodiments,processor 402 includes hardware for executing instructions, such asthose making up a computer program. Where appropriate, processor 402 mayinclude one or more arithmetic logic units (ALUs); be a multi-coreprocessor; or include one or more processors 402. In particularembodiments, memory 404 includes main memory for storing instructionsfor processor 402 to execute or data for processor 402 to operate onOneor more memory buses (which may each include an address bus and a databus) may couple processor 402 to memory 404. Bus 412 may include one ormore memory buses, as described below. In particular embodiments, one ormore memory management units (MMUs) reside between processor 402 andmemory 404 and facilitate accesses to memory 404 requested by processor402. In particular embodiments, memory 404 includes random access memory(RAM). This RAM may be volatile memory, where appropriate. Whereappropriate, this RAM may be dynamic RAM (DRAM) or static RAM (SRAM).Moreover, where appropriate, this RAM may be single-ported ormulti-ported RAM.

In particular embodiments, storage 406 includes mass storage for data orinstructions. As an example and not by way of limitation, storage 406may include an HDD, a floppy disk drive, flash memory, an optical disc,a magneto-optical disc, magnetic tape, or a Universal Serial Bus (USB)drive or a combination of two or more of these. Storage 406 may includeremovable or non-removable (or fixed) media, where appropriate. Storage406 may be internal or external to computer system 400, whereappropriate. In particular embodiments, storage 406 is non-volatile,solid-state memory. In particular embodiments, storage 406 includesread-only memory (ROM). This disclosure contemplates mass storage 406taking any suitable physical form. Storage 406 may include one or morestorage control units facilitating communication between processor 402and storage 406, where appropriate.

In particular embodiments, I/O interface 408 includes hardware,software, or both providing one or more interfaces for communicationbetween computer system 400 and one or more I/O devices. Computer system400 may include one or more of these I/O devices, where appropriate. Oneor more of these I/O devices may enable communication between a personand computer system 400. As an example and not by way of limitation, anI/O device may include a keyboard, keypad, microphone, monitor, mouse,printer, scanner, speaker, still camera, stylus, tablet, touch screen,trackball, video camera, another suitable I/O device or a combination oftwo or more of these. An I/O device may include one or more sensors.This disclosure contemplates any suitable I/O devices and any suitableI/O interfaces 408 for them. Where appropriate, I/O interface 408 mayinclude one or more device or software drivers enabling processor 402 todrive one or more of these I/O devices. I/O interface 408 may includeone or more I/O interfaces 408, where appropriate. Although thisdisclosure describes and illustrates a particular I/O interface, thisdisclosure contemplates any suitable I/O interface.

In particular embodiments, communication interface 410 includeshardware, software, or both providing one or more interfaces forcommunication (such as, for example, packet-based communication) betweencomputer system 400 and one or more other computer systems 400 or one ormore networks. As an example and not by way of limitation, communicationinterface 410 may include a network interface controller (NIC) ornetwork adapter for communicating with an Ethernet or other wire-basednetwork or a wireless NIC (WNIC) or wireless adapter for communicatingwith a wireless network, such as a WI-FI network. This disclosurecontemplates any suitable network and any suitable communicationinterface 410 for it. As an example and not by way of limitation,computer system 400 may communicate with an ad hoc network, a personalarea network (PAN), a local area network (LAN), a wide area network(WAN), a metropolitan area network (MAN), or one or more portions of theInternet or a combination of two or more of these. One or more portionsof one or more of these networks may be wired or wireless. As anexample, computer system 400 may communicate with a wireless PAN (WPAN)(such as, for example, a BLUETOOTH WPAN), a WI-FI network, a WI-MAXnetwork, a cellular telephone network (such as, for example, a GlobalSystem for Mobile Communications (GSM) network), or other suitablewireless network or a combination of two or more of these. Computersystem 400 may include any suitable communication interface 410 for anyof these networks, where appropriate. Communication interface 410 mayinclude one or more communication interfaces 410, where appropriate.Although this disclosure describes and illustrates a particularcommunication interface, this disclosure contemplates any suitablecommunication interface. In particular embodiments, bus 412 includeshardware, software, or both coupling components of computer system 400to each other. Bus 412 may include one or more buses 412, whereappropriate. Although this disclosure describes and illustrates aparticular bus, this disclosure contemplates any suitable bus orinterconnect.

Herein, reference to a computer-readable storage medium encompasses oneor more non-transitory, tangible computer-readable storage mediapossessing structure. As an example and not by way of limitation, acomputer-readable storage medium may include a semiconductor-based orother integrated circuit (IC) (such, as for example, afield-programmable gate array (FPGA) or an application-specific IC(ASIC)), a hard disk, an HDD, a hybrid hard drive (HHD), an opticaldisc, an optical disc drive (ODD), a magneto-optical disc, amagneto-optical drive, a floppy disk, a floppy disk drive (FDD),magnetic tape, a holographic storage medium, a solid-state drive (SSD),a RAM-drive, a SECURE DIGITAL card, a SECURE DIGITAL drive, or anothersuitable computer-readable storage medium or a combination of two ormore of these, where appropriate. Herein, reference to acomputer-readable storage medium excludes any medium that is noteligible for patent protection under 35 U.S.C. § 101. Herein, referenceto a computer-readable storage medium excludes transitory forms ofsignal transmission (such as a propagating electrical or electromagneticsignal per se) to the extent that they are not eligible for patentprotection under 35 U.S.C. § 101. A computer-readable non-transitorystorage medium may be volatile, non-volatile, or a combination ofvolatile and non-volatile, where appropriate.

This disclosure contemplates one or more computer-readable storage mediaimplementing any suitable storage. In particular embodiments, acomputer-readable storage medium implements one or more portions ofprocessor 402 (such as, for example, one or more internal registers orcaches), one or more portions of memory 404, one or more portions ofstorage 406, or a combination of these, where appropriate. In particularembodiments, a computer-readable storage medium implements RAM or ROM.In particular embodiments, a computer-readable storage medium implementsvolatile or persistent memory. In particular embodiments, one or morecomputer-readable storage media embody software. Herein, reference tosoftware may encompass one or more applications, bytecode, one or morecomputer programs, one or more executables, one or more instructions,logic, machine code, one or more scripts, or source code, and viceversa, where appropriate. In particular embodiments, software includesone or more application programming interfaces (APIs). This disclosurecontemplates any suitable software written or otherwise expressed in anysuitable programming language or combination of programming languages.In particular embodiments, software is expressed as source code orobject code. In particular embodiments, software is expressed in ahigher-level programming language, such as, for example, C, Perl, or asuitable extension thereof. In particular embodiments, software isexpressed in a lower-level programming language, such as assemblylanguage (or machine code). In particular embodiments, software isexpressed in JAVA, C, or C++. In particular embodiments, software isexpressed in Hyper Text Markup Language (HTML), Extensible MarkupLanguage (XML), or other suitable markup language.

Herein, “or” is inclusive and not exclusive, unless expressly indicatedotherwise or indicated otherwise by context. Therefore, herein, “A or B”means “A, B, or both,” unless expressly indicated otherwise or indicatedotherwise by context. Moreover, “and” is both joint and several, unlessexpressly indicated otherwise or indicated otherwise by context.Therefore, herein, “A and B” means “A and B, jointly or severally,”unless expressly indicated otherwise or indicated otherwise by context.

This disclosure encompasses all changes, substitutions, variations,alterations, and modifications to the example embodiments herein that aperson having ordinary skill in the art would comprehend. Similarly,where appropriate, the appended claims encompass all changes,substitutions, variations, alterations, and modifications to the exampleembodiments herein that a person having ordinary skill in the art wouldcomprehend. Moreover, reference in the appended claims to an apparatusor system or a component of an apparatus or system being adapted to,arranged to, capable of, configured to, enabled to, operable to, oroperative to perform a particular function encompasses that apparatus,system, component, whether or not it or that particular function isactivated, turned on, or unlocked, as long as that apparatus, system, orcomponent is so adapted, arranged, capable, configured, enabled,operable, or operative..

1. A method comprising: by a computing device, monitoring one or moresensors, wherein the computing device is in a locked state, and thecomputing device is associated with an authorized user of asocial-networking system; by the computing device, identifying, based oninformation associated with the authorized user, content to bedownloaded from the social-networking system, and by the computingdevice, downloading the identified content from the social-networkingsystem, wherein the identified content is stored for display after thecomputing device is unlocked.
 2. The method of claim 1, wherein thedownloading is in response to determining that an operation to unlockthe computing device is imminent, and the content comprisescommonly-viewed content.
 3. The method of claim 1, wherein thedownloading comprises downloading one or more notifications from thesocial-networking system.
 4. The method of claim 1, wherein theidentified content comprises newsfeed information.
 5. The method ofclaim 1, wherein the downloading is based on one or more previous habitsof the authorized user.
 6. The method of claim 5, wherein theinformation associated with the authorized user comprises informationindicating that the authorized user habitually checks one or more sitesor feeds.
 7. The method of claim 6, wherein the sites comprise newssites.
 8. The method of claim 6, wherein the feeds comprise RSS feeds.9. The method of claim 1, wherein the downloading is in response todetermining that the user has moved to an area that is neither theuser's home nor the user's office, and the identified content comprisesnearby points of interest for a check-in operation.
 10. The method ofclaim 1, wherein the downloading is in response to determining that theuser has traveled greater than a predetermined distance, and theidentified content comprises content from the social-networking systemfor an “around me” page.
 11. The method of claim 1, further comprising:by the computing device, receiving a request to unlock the device, therequest comprising authentication data; and by the computing device,determining whether to exit the locked state based at least in part onthe authentication data and data associated with the authorized user inthe social-networking system.
 12. One or more computer-readablenon-transitory storage media embodying software that is operable whenexecuted to: monitor one or more sensors, wherein the computing deviceis in a locked state, and the computing device is associated with anauthorized user of a social-networking system; identify, based oninformation associated with the authorized user, content to bedownloaded from the social-networking system, and download theidentified content from the social-networking system, wherein theidentified content is stored for display after the computing device isunlocked.
 13. The storage media of claim 12, wherein the downloading isin response to determining that an operation to unlock the computingdevice is imminent, and the content comprises commonly-viewed content.14. The storage media of claim 12, wherein the downloading comprisesdownloading one or more notifications from the social-networking system.15. The storage media of claim 12, wherein the identified contentcomprises newsfeed information.
 16. The storage media of claim 12,wherein the downloading is based on one or more previous habits of theauthorized user.
 17. The storage media of claim 16, wherein theinformation associated with the authorized user comprises informationindicating that the authorized user habitually checks one or more sitesor feeds.
 18. A system comprising: one or more processors; and one ormore computer-readable non-transitory storage media coupled to one ormore of the processors and comprising instructions operable whenexecuted by one or more of the processors to cause the system to:monitor one or more sensors, wherein the computing device is in a lockedstate, and the computing device is associated with an authorized user ofa social-networking system; identify, based on information associatedwith the authorized user, content to be downloaded from thesocial-networking system, and download the identified content from thesocial-networking system, wherein the identified content is stored fordisplay after the computing device is unlocked.
 19. The system of claim18, wherein the downloading is in response to determining that anoperation to unlock the computing device is imminent, and the contentcomprises commonly-viewed content.
 20. The system of claim 18, whereinthe downloading comprises downloading one or more notifications from thesocial-networking system.